CN215493060U

CN215493060U - Test device for simulating disturbance of subway operation vibration to soil around tunnel

Info

Publication number: CN215493060U
Application number: CN202120754472.1U
Authority: CN
Inventors: 李春博; 胡小荣; 蔡晓锋; 韩智云
Original assignee: Nanchang University
Current assignee: Nanchang University
Priority date: 2021-04-14
Filing date: 2021-04-14
Publication date: 2022-01-11
Anticipated expiration: 2031-04-14

Abstract

The utility model relates to a test device for simulating disturbance of subway operation vibration on soil around a tunnel, which comprises a simulation box, a subway tunnel model, a train vibration simulation device, a sensor and a data processing server, wherein the model box is formed by splicing angle steel, a steel plate and toughened glass; the subway tunnel model comprises a PEC pipe, a hard wood plate and a fixing bolt; the train vibration simulation device comprises four vibration motors which are respectively fixed on two hard wood boards in the PEC pipes; the sensors comprise displacement, soil pressure and pore water pressure sensors and are connected with the data processing server through leads. The method can simulate the disturbance condition of subway single-line and double-line operation vibration on surrounding soil under different load, buried depth and soil layer conditions; the tunnel model carries out the reduced size design according to actual subway tunnel, is pressed close to with actual engineering more, provides convenient, reliable test platform for subway operation vibration to the disturbance influence research of soil body stability and surrounding environment around the subway tunnel.

Description

Test device for simulating disturbance of subway operation vibration to soil around tunnel

Technical Field

The utility model relates to a test device for underground model, in particular to a test device for simulating disturbance of subway operation vibration to soil around a tunnel.

Background

Along with the continuous development of the industrialization degree of China, the urban road congestion phenomenon is more and more serious. In order to relieve the pressure of road congestion, the state greatly improves the construction speed of urban subways, saves a large amount of ground space for urban traffic, relieves the traffic pressure, and promotes the development of the whole city on the basis of an economic zone of a subway line. While the subway brings convenience to life of people, the cyclic load generated by train vibration brings deformation settlement to the ground of an operation area and can cause the settlement of the foundation of surrounding buildings. In severe cases, the settlement and deformation around the tunnel and even the vibration and liquefaction phenomena can be caused, the ground subsidence is caused, and the social safety is seriously influenced. In addition, the vibration can be transmitted to surrounding buildings through soil bodies and communicated with the foundation in the form of waves, so that the influence is not negligible, and the vibration has attracted attention at home and abroad. Therefore, the research on the vibration effect of the subway train and the deformation and settlement mechanism of the surrounding soil body has important significance for guiding the subway tunnel construction and controlling the soil body settlement after the subway operation.

In the aspect of subway train operation vibration simulation, few model test devices which are simple and easy to operate are needed. With the improvement of the utilization rate of the subway, the analysis of mechanical characteristics and microscopic changes of surrounding soil bodies caused by subway tunnel vibration becomes a fundamental guarantee for the long-term operation of the urban subway. On the other hand, the practical size model adopted for subway operation at present has high simulation difficulty and high economic cost, and the structural state of the natural underground soil body is difficult to control, so that the operation condition of the double-line subway with different soil qualities is difficult to simulate.

SUMMERY OF THE UTILITY MODEL

In order to overcome the defects in simulation in the prior art, the utility model aims to provide the test device for simulating the disturbance of the subway operation vibration on the soil around the tunnel, which can simulate the vibration of a subway train during operation more truly and conveniently and provide an effective and feasible test device for researching the problems of deformation, settlement, vibration, liquefaction and the like of the ground of an operation area and the soil around the tunnel in subway operation.

In order to achieve the purpose, the utility model adopts the following technical scheme:

a test device for simulating disturbance of subway operation vibration on soil around a tunnel comprises a simulation box, a subway tunnel model, a train vibration simulation device, a sensor and a data processing server;

the model box comprises angle steels, steel plates and toughened glass, the top of the model box is open, the bottom of the model box is provided with one steel plate, four corners of each steel plate are vertically and respectively fixed with one angle steel, and the toughened glass is arranged between every two adjacent angle steels to form a four-way closed model box;

the subway tunnel model comprises PEC pipes, two hard boards and fixing bolts, wherein the hard boards are fixed in the PEC pipes through the fixing bolts, and the PEC pipes are parallelly buried in a model box;

the train vibration simulation device comprises four vibration motors, wherein every two vibration motors are in a group and are respectively fixed on the hard wood boards in the two PEC pipes through bolts;

the sensor comprises a displacement sensor, a soil pressure sensor and a pore water pressure sensor, the sensor is buried in soil near the subway tunnel model and is connected with a data processing server through a lead, and the data processing server converts and processes received data.

And a steel bracket base is arranged below each of the four corners of the steel plate and is welded and fixed with the steel plate to separate the simulation box from the ground.

The steel plate at the bottom of the model box is fixedly welded with the angle steel frame, toughened glass is embedded between the angle steels, and rubber pads are arranged at the contact positions of the toughened glass and the steel plate at the bottom of the model box and the contact positions of the toughened glass and the angle steels.

The displacement sensor is a laser displacement sensor, and the measuring range is as follows: 20mm, linear precision: ± 0.02% F.S =16 μm; the soil pressure sensor has the following measuring range: 20Kpa, linear accuracy: 0.1 KPa; pore water pressure sensor, range: 15KPa, linear precision: 0.075 KPa.

The data processing server is a 60-channel strain test analyzer.

The vibration motor is fixed on the hard wood board and is connected in series to the power supply rotating speed controller through a lead to adjust the output load of the power supply rotating speed controller.

The utility model has the beneficial effects that:

1. the required materials are simple and easy to obtain, the size of the model box is not large, and the method is suitable for indoor tests;

2. the method can simulate the vibration response of the double-track subway under different vibration loads, different tunnel burial depths and different train operation states;

3. the method can be used for simulating the vibration of the double-line subway and is suitable for the vibration research of the subway under the complex working condition;

4. the tunnel model is designed according to the actual subway tunnel in a reduced size, is closer to actual engineering, and provides a convenient and reliable test platform for the disturbance influence research of subway operation vibration on the stability of the soil body around the subway tunnel and the surrounding environment.

Drawings

FIG. 1 is a schematic structural diagram of a test device for simulating disturbance of subway operation vibration on soil around a tunnel according to the present invention;

FIG. 2 is a cross-sectional view taken at section I-I in FIG. 1;

FIG. 3 is a cross-sectional view of section II-II of FIG. 1;

in the figure: 1. angle steel; 2. tempering the glass; 3. a steel plate; 4. a steel bracket base; 5. a PEC tube; 6. a vibration motor; 7. a hard wood board; 8. a sensor; 9. and (5) fixing the bolt.

Detailed Description

In order to better explain the present invention, the detailed description of the present invention is made below with reference to the accompanying drawings and examples.

Example (b): see fig. 1-3.

As shown in fig. 1, a test device for simulating disturbance of subway operation vibration to soil around a tunnel includes a model box, a subway tunnel model, a train vibration simulation device, a sensor 8 and a data processing server.

The model box is formed by splicing angle steel 1, a steel plate 3 and toughened glass 2, and the bottom of the model box is provided with the steel plate 3, so that the box bottom is not easy to be damaged by vibration and leak water during circulating vibration, and has certain pressure bearing capacity; the periphery of the model box is embedded by adopting the organic toughened glass 2, so that the settlement of the soil body and the deviation of the internal soil body can be conveniently observed; particularly, the joint of the steel plate 3 and the toughened glass 2 is protected by a rubber pad due to different materials, so that glass breakage caused by strong vibration can be prevented; and filling and arranging the whole model box according to the buried depth of the tunnel required by the research.

The subway tunnel model is composed of PEC tubes 5 and hard boards 7, the hard boards 7 are used for simulating a subway track, and the hard boards 7 and the PEC tubes 5 are fixed by punching holes through fixing bolts 9, so that the PEC tubes 5 and the hard boards 7 are fixed into an integral tunnel; PEC tube 5 and solid wood 7 are fixed as shown in FIGS. 1-3, and the holes are drilled in the middle of the pipe by long bolts, and transverse screws are inserted into the positions of both sides of the pipe contacting the solid wood 7 by the same technique. The subway tunnel model is reduced according to the actual size, the ratio is 1:30 (relevant professionals can adjust the model size according to the content of the utility model according to different laboratory conditions), the diameter of the PEC pipe 5 is 30cm, the thickness is 1.5cm, the total length is 1.1m, the total length of the hard wood board 7 in the tunnel is 0.9m, and the thickness is 2 cm.

The train vibration simulation device comprises four vibration motors 6 and a speed regulating device; two vibrating motors 6 are arranged in each subway tunnel model, are fixed on a hard wood board 7 in the tunnel by bolts and are connected in series to a speed regulating device by a lead, and the speed regulating device is a power supply rotating speed controller; and providing power for the train model in a resonance mode. The output load of the vibration motor 6 adopted by the utility model is 25N/piece, and the selection method comprises the following steps:

the proportion of the taken subway tunnel model is 1:30, one carriage is simulated by two vibrating motors 6, the actual full load of the subway single carriage is 4.5 tons, the vibrating load of the vibrating motors 6 is 0.075 ton/one is obtained by conversion according to the proportion, according to the simulation regulation of engineering test load, the similarity coefficient 1/30 still needs to be multiplied, the real output load of the vibrating motors 6 required by the test model is 0.0025 ton/one is obtained, and the vibrating motor 6 with the vibrating force of 2.5 kg/one is selected to be most suitable (if a later-stage researcher modifies the model size, the vibrator load can still be calculated according to the method).

The sensor 8 is a device displacement measuring sensor and a soil pressure measuring sensor; the displacement measuring sensor is a laser displacement sensor, and the high-precision sensor can more clearly measure the displacement change in the soil body, the settlement of the soil body and the settlement of the tunnel under the vibration load; the soil pressure measuring sensor comprises a high-precision soil pressure and high-precision pore water pressure sensor;

the performance of the laser displacement sensor is as follows: "measuring range: 20 mm; linear precision: (± 0.02% F.S. =16 μm); reproducibility accuracy: 0.25 μm; sampling frequency: 2.55/5/10/20/100/200/500/1000 μ s;

the performance of the high-precision soil pressure sensor is as follows: "measuring range: 20 Kpa; linear precision: 0.1KPa

The performance of the high-precision pore water pressure sensor is as follows: "measuring range: 15 KPa; (2) linear precision: 0.075KPa "

The data processing server consists of a 60-channel strain test analyzer, and is used for connecting the selected laser displacement sensor, the soil pressure sensor and the pore water pressure sensor to the strain test analyzer, receiving monitoring data of displacement, soil pressure and pore water pressure, and performing data conversion and processing.

In summary, the specific process of the simulation test of the present invention is as follows:

(1) soil sample preparation

Soil is taken from the vicinity of the subway tunnel construction site, a soil sample is dried in the sun, and soil blocks are crushed and screened according to the required particle size distribution. And filling in layers according to the compactness required by the test, wherein the filling thickness is different according to different tunnel burial depths. And (4) according to the field soil sample, burying soil bodies with different properties.

(2) Arrangement of sensors

The arrangement of the sensors 8 is shown in figures 1-3, the utility model is designed symmetrically, and only one side of the sensor 8 is needed to be arranged; the required sensors 8 include laser displacement sensors, soil pressure sensors, pore water pressure sensors.

(3) Filling soil for model box

The height of the model box is 1.35m, and the soil covering heights of the test are 1m, 1.1m and 1.2m respectively. The corresponding tunnel burial depth preparations are 0.5m, 0.55m and 0.6m respectively. The arrangement and arrangement of the sensors 8 varies with the depth of burial. And filling in layers according to the compactness required by the test, wherein the filling thickness is different according to different tunnel burial depths.

After the soil is filled to the position of each layer of the sensor 8 to be arranged, the sensor 8 is arranged according to the point positions shown in figures 1-3, and after each layer of the soil is filled, the soil body is treated according to the required saturation. And standing after the soil body is completely filled, and solidifying under the action of gravity.

(4) Sensor and tunnel inspection and placement

The sensor 8 and the subway tunnel model are placed at corresponding positions in the soil layer filling process, and the working state of the sensor 8 (including power supply voltage, preheating time storage, binding of wires, wiring positions and connection modes, and signal end reading) needs to be checked in time. After the filling is finished, a certain number of displacement sensors are arranged on the soil layer according to the requirement.

The following concrete examples are several working conditions under which the test device of the utility model simulates the operation of a two-line subway:

1. simulating tunnel buried depth change effect

The height of the novel experimental model box of the experiment is 1.35m, the thickness of the upper portion of the initial tunnel is filled with covering soil to be 0.5m, and the underground working condition of the actual 6m buried depth can be simulated according to the scaling of 1: 12. After the arrangement is completed according to the steps, the vibration frequency is adjusted to be 0.5Hz, the server and the vibrator power supply are turned on, and the readings of various sensors are automatically recorded every 5 min. And after the test is finished, the power supply and the server of the vibrator are closed. And continuously filling soil until the thickness reaches 0.6m, and simulating the actual underground working condition of 7.2m buried depth. And after the soil covering is finished, the displacement sensor connecting switch and the server are turned on, and the soil displacement settlement data is recorded every 5 min. After the data are stable, starting the test system, adjusting the vibration frequency of the vibration motor 6 to be 0.5Hz, turning on a server and a vibrator power supply, and automatically recording the readings of various sensors 8 every 5 min. And after the test is finished, the power supply and the server of the vibrator are closed. And continuously filling soil until the thickness reaches 0.7m, and simulating the actual underground working condition of 8.4m buried depth. And after the soil covering is finished, the displacement sensor connecting switch and the server are turned on, and the soil displacement settlement data is recorded every 5 min. After the data are stable, starting the test system, adjusting the vibration frequency of the vibration motor 6 to be 0.5Hz, turning on a server and a vibrator power supply, and automatically recording the readings of various sensors 8 every 5 min. And after the test is finished, the power supply and the server of the vibrator are closed. And monitoring the displacement change of the tunnel after each filling, and performing the test after the settlement of the tunnel is stable.

2. Simulating the effect of tunnel vibration frequency

And covering soil above the tunnel to be filled to the thickness of 0.6m, and simulating the actual underground working condition of 7.2m buried depth. After the system is installed, the simulation effect can be achieved only by changing train load vibration and setting the operation state of the double-track tunnel (two trains operate simultaneously, only one train operates and two trains operate at a certain time interval) according to test requirements. The test system is started for the first time, the vibration frequency of the vibration motor 6 is adjusted to be 0.5Hz, the server and the vibrator power supply are turned on, and the readings of various sensors are automatically recorded every 5 min. And after the test is finished, the power supply and the server of the vibrator are closed. And starting the test system for the second time, adjusting the vibration frequency of the vibration motor 6 to be 1Hz, starting a server and a vibrator power supply, and automatically recording the readings of various sensors every 5 min. And after the test is finished, the power supply and the server of the vibrator are closed. And starting the test system for the third time, adjusting the vibration frequency of the vibration motor 6 to be 2Hz, turning on a server and a vibrator power supply, and automatically recording the readings of various sensors every 5 min. And after the test is finished, the power supply and the server of the vibrator are closed.

The device disclosed by the utility model is used for carrying out reduced size simulation according to the actual condition of the subway, and is provided with a double-line subway tunnel model, so that the device can be widely applied to scientific research in the directions of dynamic response and the like of urban soft soil tunnel engineering. By depending on subject advantages and a test platform, scientific research and engineering personnel can fully carry out systematic research on the response problem of the subway operation vibration environment, explore the vibration deformation mechanism of a subway tunnel structure and surrounding soil bodies, guide engineering practice, improve subway trip safety and optimize rail transit construction.

The foregoing processes describe the basic principles, principal features and advantages of the utility model. It will be understood by those skilled in the art that the present invention is not limited by the foregoing examples, which are provided to illustrate the principles of the utility model, and that various changes and modifications may be made without departing from the spirit and scope of the utility model, which is intended to be protected by the following claims. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims

1. The utility model provides a test device of simulation subway operation vibration to soil body disturbance around tunnel, includes simulation case, subway tunnel model, train vibration analogue means, sensor (8) and data processing server, its characterized in that:

the model box comprises angle steels (1), steel plates (3) and toughened glass (2), the top of the model box is open, the bottom of the model box is provided with one steel plate (3), four corners of each steel plate (3) are vertically fixed with one angle steel (1), and the toughened glass (2) is arranged between two adjacent angle steels (1) to form a four-way closed model box;

the subway tunnel model comprises PEC tubes (5), two hard wood plates (7) and fixing bolts (9), wherein the hard wood plates (7) are fixed in the PEC tubes (5) through the fixing bolts (9), and the PEC tubes (5) are parallelly buried in a model box;

the train vibration simulation device comprises four vibration motors (6), wherein every two vibration motors (6) form a group and are respectively fixed on hard wood boards (7) in two PEC pipes (5) through bolts;

the sensor (8) comprises a displacement sensor, a soil pressure sensor and a pore water pressure sensor, the sensor (8) is buried in soil near the subway tunnel model and is connected with the data processing server through a wire, and the data processing server converts and processes received data.

2. The test device for simulating the disturbance of the subway operation vibration to the soil around the tunnel according to claim 1, wherein a steel bracket base (4) is arranged below each of four corners of the steel plate (3), and the steel bracket bases (4) are welded and fixed with the steel plate (3) to separate the simulation box from the ground.

3. The test device for simulating the disturbance of subway operation vibration to the soil around the tunnel according to claim 1, wherein the model box bottom steel plate (3) and the angle steel (1) frame are welded and fixed, the tempered glass (2) is embedded between the angle steels (1), and rubber pads are arranged at the contact positions of the tempered glass (2), the model box bottom steel plate (3) and the angle steel (1).

4. The test device for simulating the disturbance of the subway operation vibration on the soil around the tunnel according to claim 1, wherein the displacement sensor is a laser displacement sensor, and the measuring range is as follows: 20mm, linear precision: ± 0.02% F.S =16 μm; the soil pressure sensor has the following measuring range: 20Kpa, linear accuracy: 0.1 KPa; pore water pressure sensor, range: 15KPa, linear precision: 0.075 KPa.

5. The test device for simulating the disturbance of the subway operation vibration on the soil around the tunnel according to claim 1, wherein the data processing server is a 60-channel strain test analyzer.

6. The test device for simulating the disturbance of subway operation vibration on the soil around the tunnel according to claim 1, wherein the vibration motor (6) is fixed on a hard wood board (7) and is connected in series to a power supply rotation speed controller through a lead to adjust the output load of the power supply rotation speed controller.